The prinicpal objective of the Boston University Medical Center's Core Center for Endocrine-Diabetes-Metabolic Research is to promote the efforts of a large number of scientists engaged in studies on humoral factors in disease by controlled observations and metabolic parameters. The ultimate goals of this Center will be to improve methods for diagnosis, treatment and prevention of a variety of metabolic disorders in man including the metabolic alterations of diabetes mellitus, hypertension, rheumatoid disease, and hormone-dependent cancer of the breast. We believe that it is our purpose to facilitate these efforts by a coordination of approaches to the study of patients in a single research facility with prinicpal Core functions: (1) Core clinical facility, including an 8 bed discrete unit staffed with metabolic research projects. (2) The core laboratory unit to provide the collection, measurement and aliquoting of a variety of biological fluids obtained by the various investigators involved in projects both on the core clinical facility and in the outpatient service. This laboratory facility would also provide commonly used radioimmunoassay measurements and other radio-enzymatic procedures. (3) A core administrative unit to monitor the day-to-day operation of administrative unit would be to encourage the interaction of the various investigators conducting projects in the core clinical facility and the core laboratory facility.